The district also includes small parts of the following towns: East Fishkill, Hyde Park, Pawling, and Wappinger.

[3] Census-designated places (hamlets) within this district include Arlington, Freedom Plains, MacDonnell Heights, Pleasant Valley, Titusville, and Vassar College, as well as portions of Red Oaks Mill.

The program permits the student to earn up to 15 credits while fulfilling the basic Regents Prep courses in history and mathematics[6] Senior Follies is an Arlington High School Tradition that dates back to the 1970s.

The Arlington High School music department currently supports 5 concert bands, 5 orchestras, 2 choirs, 3 jazz ensembles (with the most competitive being Jazz Machine), a competitive marching band, an indoor color guard, and numerous instrumental and vocal chamber ensembles.

In October 2019, for the fourth year in a row, the Arlington Admirals High School Marching Band brought home the first place trophy, or Governor’s Cup, in the National Class from the New York State Field Band Conference Championship, held annually in Syracuse.

The original building constructed specifically to house Arlington High School was built on Raymond Avenue in Poughkeepsie.

The current Arlington High School building, originally constructed in 1961, has been significantly expanded several times, most recently in 2009.

In 1979, the current high school became "North Campus" for juniors, seniors and a portion of the sophomore class, while the former LaGrange Junior High School, located a short distance away on Stringham Road in Lagrangeville, was re-designated "South Campus" and housed freshman and the rest of the sophomore class.

Another renovation was completed at the high school in the Autumn of 1998 that nearly tripled its size, enabling all four grades to be moved back to what had been the North Campus.

Debate over the expansion was tense, due to the perception of already lofty school-tax rates and the looming energy crisis.

The expansion includes 40 new classrooms, a K-12 education center, a new TV studio, a radio station as well as new science labs, a new auditorium, and a cafeteria for seniors.

The expansion was added onto the school's south end of the 1100s and encompasses the previous senior parking lot.

The William J. Sweeney Performance Hall has opened and was first used for the Admiral Players' production The Wedding Singer and the 2010 Winter Concert Series.